Monoterpene ketones

Variant 1 Dissolve 0.8 g 4-(dimethylamino)-benzaldehyde in a mixture of 90 ml 95% ethanol and 10 ml 98% sulfuric acid [9]. For monoterpene ketones Dissolve 200 mg 4-(dimethylamino)-benzaldehyde in 20 ml cone, sulfuric acid [14]. 

Monoterpenes lb 448 Monoterpene glucosides la 327,328 Monoterpene hydrocarbons la 76 Monoterpene ketones lb 252-254 Monuron lb 252,418 Morazone la 45 Morgan-Elson reagent lb 63 Morin la 44,91... 

On heating with either acid or base, the monoterpene ketone isodihydrocarvone is largely converted into one product only, its stereoisomer dihydrocarvone. 

Piperitone, with its fresh minty camphor4ike odor, is present in various leaf essential oils. Among Mentha and Eucalyptus genera, there are piperi tone-rich species which are considered common sources of this natural monoterpene ketone. The (45) (-f)- enantiomer was reported to be... 

Madyastha KM, Xhulasiram HV, Xransformation of a monoterpene ketone, (i )-(-b) puiegone, a potent hepatotoxin, in Mucor piriformk, J Agric Food Chem, 47 1203-1207, 1999. 

Ali, M.S. et al., A chlorinated monoterpene ketone, acylated (J-sitosterol glycosides and a flavanone glycoside from Mentha longifolia (Lamiaceae), Phytochemistry, 59, 889, 2002. 

The monoterpene ketones menthone and isomenthone [159, 166] exhibited OH- radical scavenging activity. Depending on the method employed, different activities for anethole have been reported [153, 169]. 

Z-Tagetone (82a) -Tagetone (82b) Z-Ocimenone (83a) -Ocimenone (83b) Fig. (13). Acyclic monoterpene ketones tagetone and ocimenone... 

As in the discussion of the acyclic monoterpene ketones (see 1.1.3) instead of the sesquiterpene ketones, the structurally related compounds neryl-(176) and geranylacetone (169) will be reviewed. Indeed, as mentioned before, neryl- and geranylacetone are the norsesquiterpene -analogues of 6-methyl-5-hepten-2-one, which is the /1-oxidation product of nerol and geraniol, just like neryl- and geranylacetone are the bioconversion products of famesol (see 2.1.1). 

Ali MS, Saleem M, Ahmad W, Parvez M, Yamdagni R (2002) A Chlorinated Monoterpene Ketone, Acylated (3-Sitosterol Glycosides and a Flavanone Glycoside from Mentha longifolia (Famiaceae). Phytochemistry 59 889... 

Fig. 8 Monoterpene ketones carvone, geranial, neral, and citronellal together geranial and neral make up citral...

Essential oil recovery and composition showed variation with maturity. C. sativum L. fruits grown in Tunisia gave essential oils at the initial, middle and final stages of maturity, with yields of 0.01, 0.12 and 0.35%, respectively. Essential oil at the first stage of maturity consisted mainly of monoterpene alcohols (14.6%), especially linalool (10.96%). Other constituents were monoterpene aldehydes (2.07%), ethers, hydrocarbons and monoterpene ketones, as well as phenols and sesquiterpenes. 

The metabolism of 7-endo-fenchol to ci-fenchone in fennel has been studied in quite some detail by Croteau and co-workers (Croteau and Felton, 1980). Croteau et al. (1980a) later reported a soluble enzyme preparation from the leaves of fennel which catalysed the cation-dependent cyclization of both geranyl pyrophosphate and neryl pyrophosphate to the bicyclic rearranged monoterpene 1-enc/o-fenchol. Croteau et al. (1980b) found that (+)-(lS)-fenchone, an irregular bicyclic monoterpene ketone thought to be derived... 

A monoterpenone, or monoterpene ketone, is a monoterpene with a ketone functional group. 

Figure 3.9 Ketones. /-Carvone (C10H140), a monocyclic monoterpene ketone. Courtesy Spiring Enterprises Ltd.

Monocyclic monoterpene ketone monooxygenase Rhodococcus erythropolis DCL 14 1 single polypeptide NADPH 60 FAD 9.0 [51]... 

Three cinnamic acid derivatives (305-307) were isolated from the rhizomes of K. galanga [273]. Compound 306 was also found in the extract of AT. pulchra [271]. Ethyl /j-methoxycinnamate (306) was reported to inhibit monoamine oxidase [248] and to have cytotoxic activity [251]. Cinnamic acid derivatives obtained from K. galanga were shown to possess larvicidal activity [273]. Ethyl cinnamate as well as ethyl p-methoxycinnamte from the rhizomes of K. galanga was highly toxic against larvae of Spodoptera littoralis [159]. A monoterpene ketone, 3-... 

CioHiftO, Mr 152.24, oil, bp. 182-183 C. A. and its isomer iso-A. (2,5,5-trimethyl-l,6-heptadien-4-one) are monoterpene ketones for which, as yet, no practical uses have been found. 

C,oH,jO, Mr 152.24, oil with a menthol-like odor. Bi-cyclic monoterpene ketones with the thujane structure occurring in two C-4-epimeric forms in nature i SAR,5R) -)-a-T, bp. 83.8-84.1 °C (17 hPa), [a]o -19.2° (neat), (15, 4S,5/ )(+)-)S-T., bp. 85.7 -86.2°C (17 hPa), [a]o +72.5° (neat). Not only the names a-and jS-thuJone but also thujone and isothujone are sometimes used incorrectly in the literature. T. are potent neurotoxins, cause epileptic seizures, and can lead to severe psychic damage. It is not yet known if both epimers exhibit the same biological effects. Occurrence Very widely distributed in the essential oils of Asteraceae, Cupressaceae, Lamiaceae, Pina-ceae species. Thuja oil (Thuja occidentalis, Cupressaceae) contains 40% (-)-a-T. and tansy oil (Tanace-tum vulgare, Asteraceae) 58% (+)-/S-T. 

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